Infection with Schistosoma mekongi in Southeast Asian refugees

Schistosoma mekongi is a newly recognized species of Schistosoma that is closely related to Schistosoma japonicum and is pathogenic to humans. Like the other forms of schistosomiasis in which the parasites reside in the mesenteric vasculature, S. mekongi infection has hepatosplenomegaly and portal venous hypertension as its most common serious sequelae. Schistosomiasis, although endemic in certain areas of Southeast Asia, has not been recognized as a health problem in Asian refugees who are currently entering the United States. In the present study 12 Laotian immigrants with S. mekongi infection were examined. The clinical, laboratory, and parasitologic findings in these patients are discussed. The diagnosis was made by examination of stool specimens in 11 patients and rectal biopsy specimens in one patient. All patients were asymptomatic, although the six youngest children had hepatomegaly. It is suggested that specific serologic tests may be useful in screening Asian refugees for infection with Schistosoma.